Check if an array of strings contains a substring of a given string in javascript?

Question

I have the following string:

var teststring = "Hello"

I have the following array of strings:

var listofstrings = ["Hellothere", "Welcome", "Helloworld", "Some String"];

I want to have inside of a conditional, a simple check to return if any thing in 'listofstrings' matches any part of 'teststring'. The following is the pseudocode:

if(teststring.indexOf(any-part-of-listofstrings) > -1)

How can I accomplish this? The simplest way I can think of is for looping it, but am looking to see if there is a better way.

By for looping, I mean multiple lines like:

for(var i = 0; i < listofstrings.length; i++) {
 if(teststring.indexOf(listofstrings[i] > -1) {
 return true;
 }
}

The above takes up multiple lines seems too complex for what I am trying to do...

• Rolando: @Dan that question does not address my question. The answer in that question requires an exact match to the entire string. If you modified the example in answer to ["I", "like", "turtles love me"], then it breaks and returns false. I want to return true in that case because turtles was part of the substring of at least one of the items in the array.
• Code-Apprentice: This is not built into JavaScript. You will have to write a function to do this yourself.
• ibrahim mahrir: The question is not a duplicate of the suggested link. Please don't vote to close.

Answer 1

You can use Array#some, and to make things shorter, use an arrow function and String#includes instead of String#indexOf:

if(listofstrings.some(str => teststring.includes(str))) {
 // found one
}

• Rolando: This is shorter and less complex than a for loop for sure. If anyone has even better/shorter ways of doing this, please share. Perhaps someday, Javascript will have some built in function to handle this.